LACTIC-ACID FERMENTATION OF MUSHROOM (AGARICUS-BISPORUS) FOR PRESERVATION AND PREPARATION OF SAUCE

Introduction of lactic acid fermentation into mushroom (Agaricus bispo rus) and preparation of sauce from fermented mushrooms was studied as a method of extension of its postharvest life. Mushrooms (blanched or unblanched) with dry salting, similar to the sauerkraut preparation, d id not undergo lactic acid fermentation. The amount of acid produced w as negligible (0.03-0.04%) and the pH did not reduce below 4.39 and it was higher than the microbiologically critical value (pH 4.1). Mushro oms of all these treatments got spoiled within 24 h with microbial cou nt ranging from 4.0x10(4) to 15x10(8). Even the addition of lactose di dn't stimulate lactic acid fermentation in dry salting procedure. Mush room-in-brine inoculated with lactic acid bacteria produced more acid than the uninoculated mushroom. Amongst the bacteria tried, Lactobacil lus plantarum produced the highest amount of acid (0.59%) after 5 days of fermentation. The bacterium sharply decreased the pH to less than 4.0 in one day. Two % salt supported the higher acid production than 3 %. Fermentation softened slightly the spongy texture of mushrooms with out altering the colour and flavour of fermented mushrooms. The fermen ted mushroom along with brine could successfully be converted into sau ce of desirable physico-chemical characteristics, sensory qualities an d shelf life. The method of preparation and quality characteristics of mushroom sauce are also described.